Receptor binding of cholecystokinin analogues in isolated rat pancreatic acini.
The receptor binding of CCK analogues was determined in terms of the inhibition of [125I]CCK binding in isolated rat pancreatic acini. The inhibition curve produced by CCK-8 showed the same feature as that produced by synthetic human CCK-33. The relative potency values of CCK analogues to half-maximally inhibit specific CCK binding were calculated; CCK-8 was equal to human CCK-33, 3-fold stronger than natural porcine CCK-33 and 39, and 700-fold stronger than the unsulphated form of synthetic human CCK-33. Our data suggest that CCK-33, one of the longer molecular forms of CCK, is as important as CCK-8 in the mechanism of physiological actions of CCK.
Doi
R
R
First Department of Surgery, Faculty of Medicine, Kyoto University, Japan.
Hosotani
R
R
Inoue
K
K
Fujii
N
N
Yajima
H
H
Rayford
P L
PL
Tobe
T
T
D000818:Animals; D001667:Binding, Competitive; D002766:Cholecystokinin / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D010179:Pancreas / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011949:Receptors, Cholecystokinin / Q000378:metabolism*
D011949:Receptors, Cholecystokinin; D002766:Cholecystokinin